Preserving Our Oaks: Celebrating Earth Day with Cryopreservation at CREW

Posted April 22, 2024 by Aislyn Tyler

Happy Earth Day! This incredibly special day is for celebrating and appreciating the natural world around us. Read on to learn about the research being conducted at the Lindner Center for Conservation and Research of Endangered Wildlife (CREW) this Earth Day.

Collection season at the CREW Plant Division is in full SPRING! Plant scientists at CREW partner with organizations across the United States during the spring to collect cuttings from threatened oak species. These efforts support our ongoing IMLS grant, which focuses on developing oak tissue culture and cryopreservation techniques. Cryopreservation is the process of freezing and storing plant tissues or seeds in liquid nitrogen (-196°C or -320°F). CREW focuses primarily on cryopreserving shoot tips, which are the growing stem cells from plants grown in culture.

photo of cryobiobank at crew

First, oak cuttings are delivered and processed; they are sterilized in a bleach solution. Then, the oak shoots are put into an additional fungicide and rinsed in sterile water before being put into culture on nutrient-rich medium. After close watch for contamination, the test tube oaks that survive can be transferred to a hormone medium, which instructs the plant to produce tons of new shoots. The shoot tips are then isolated and can be cryopreserved.

Oaks cannot be seed banked using conventional methods, therefore cryopreservation of shoot tips is the only way to bank this species. In the event of population decline, CREW’s frozen garden would provide a backup and contribute to the restoration of threatened plant populations.

Oaks at all different stages of growth: